Lewis & Short

ĭnānĭtas, ātis, f. [inanis].

  1. I. Lit., emptiness, empty space (rare but class.): mihi inanitate Jamdudum intestina murmurant, Plaut. Cas. 4, 3, 5: per inanitatem ferri, Cic. Fat. 9, 18: oris, Quint. 1, 11, 6.
  2. II. Trop., emptiness, uselessness, inanity (rare but class.): amputata circumcisaque inanitate omni, Cic. Fin. 1, 13, 44; id. Tusc. 3, 2, 3: verborum et imaginum, Gell. 13, 8, 2.